** Genetics testing firm Tempus AI's shares TEM.O fall 8.2% to $67.75

** Stifel cuts to "hold" from "buy"; raises price target to $65 from $45

** Brokerage says the valuation of stock looks stretched, after company commentary suggested 2025 outlook for core business might be guided below Street expectations

** Brokerage says co's acquisition of Ambry Genetics will be positive to overall business

** But it expects TEM's revenue growth to slow, especially in the data segment; points to the slower growth profile of Ambry's hereditary cancer testing market

** Avg rating of brokerages is a "buy"; median PT is $52 - LSEG data

** As of last close, TEM has risen 84.3% since its June 14 debut on Nasdaq

(Reporting by Sukriti Gupta in Bengaluru)

((Sukriti.Gupta@thomsonreuters.com;))